Speleothems (calcite formations such as stalagmites in caves) always incorporate trace amounts of uranium during their growth. However, in seepage waters and in recently crystallized calcite the uranium present shows considerable enrichment of the daughter isotope ²34</sup relative to its parent ²38</sup, and only negligible amounts of ²³⁰Th activity. It takes about a million years until the radioactive equilibrium in the uranium series is established in speleothems. This information when applied with Á8-spectrometric methods described is useful in the dating of fossils and prehistoric human relics (including bone material). -- AATA -- AATA